If the trees areIf the trees are container-grown or balled-and-burlapped (not bare-root), you can plant them in fall or early spring, when they are dormant. Bare-root trees should be planted in late winter/early spring, while the plants are dormant. For tips on how to plant trees correctly, where to site them, etc., you might check with your county’s Cooperative Extension. See: http://www.almanac.com/content/cooperative-extension-services